The inventive concepts relate to a semiconductor memory device and more particularly, to a semiconductor memory device having improved refresh characteristics.
A dynamic memory device such as a dynamic random access memory (DRAM) stores data in the form of charges. The stored charges deteriorate due to a leakage current. In this case, the data stored in the memory device may be lost. Thus, before the data is lost, the data needs to be read from a memory cell and the memory cell needs to be charged again according to the read data. The data stored in the memory cell is retained by repeating this process.